1. Field of the Invention
The present invention generally relates to semiconductor memory devices, and more particularly to a video data arrangement in a memory device with efficient memory bandwidth usage and efficient memory data access.
2. Description of the Prior Art
Memory bandwidth is the rate at which data can be stored to or read from a semiconductor memory device, and is usually expressed as bytes per second. As the memory resource is usually precious in an electronic system in which the memory device or devices are shared among a variety of processors or devices, a lack of memory bandwidth is commonly experienced. One way to increase the memory bandwidth is to sequentially and continuously access an entire block of data during which the memory device is given exclusive access to a particular processor or device. For example, in a burst mode, as provided by some memory devices, a whole block of data can be transferred without interruption once the first access address and some required control signals are provided to the memory device. Nevertheless, the memory device is oftentimes accessed in a random manner with the required data being randomly stored into or read from distinct locations of the memory device. In this case, memory bandwidth usage can be inefficient owing to substantial time being wasted in providing access addresses and control signals during each data access.
The disadvantage of randomly accessing data of a memory device becomes even worse when the memory device is utilized as a video buffer (or frame buffer) for storing video data (particularly high-density video data) or when real-time image processing is involved.
For the reason that memory device bandwidths tend to be inefficient in video data access operations even to the extent of incapacitating real-time image applications, a need has arisen to propose a novel scheme for increasing the efficiency of such operations in memory devices.